Immersion heater



FIG. 1 is a perspective view of an immersion heater showing our new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a front elevational view thereof

FIG. 5 is a back elevational view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The dashed broken lines appearing in the figures are for the purpose of illustrating portions of the immersion heater that form no part of the claimed design.

The dot dash line appearing in FIG. 7 is for the purpose of illustrating the bounds of the claim and forms no part thereof. 

CLAIM The ornamental design for an immersion heater, as shown and described. 